Thermal and magnetic propertiesof selected Fe-based metallic glasses

Purpose: The work presents a thermal stability characterization and soft magnetic properties analysis of selected Fe-based metallic glasses. Design/methodology/approach: The studies were performed on ribbons prepared by the planar flow casting technique, which is a method of continuous casting of the liquid alloy on a surface of turning copper based wheel. The methods of X-ray diffraction were used for the qualitative phase analysis. The thermal properties associated with crystallization temperature of the glassy alloys were measured using the differential thermal analysis. The magnetic properties were determined by the Maxwell-Wien bridge, fluxometer and VSM methods. Findings: The studied Fe72B20Si4B4 and Fe36Co36B19Si5Nb4 metallic glasses in as-cast state were fully amorphous. The Curie temperature (Tc) for Fe72B20Si4B4 alloy has a value of 582 K and Fe36Co36B19Si5Nb4 has higher Tc, which has a value of 605 K. The obtained magnetic properties allow to classify the studied amorphous alloys in as-cast state as soft magnetic materials. The coercive field of tested alloys has a value about 8 A/m. The maximum magnetic permeability of Fe72B20Si4B4 alloy (!max = 21500) is much higher than Fe36Co36B19Si5Nb4 metallic glasses (!max = 3200). Similarly, saturation magnetization of Fe72B20Si4B4 alloy (Bs = 1.04 T) is higher than Fe36Co36B19Si5Nb4 (Bs = 0.99 T) amorphous alloy. Practical implications: The studied glassy alloys are suitable materials for many electrical application in different elements of magnetic circuits and for manufacturing of sensors and precise current transformers. Originality/value: The obtained results confirm the utility of applied investigation methods in the thermal and magnetic properties analysis of examined amorphous alloys

Markovian MC simulation of QCD evolution at NLO level with minimum k_T

We present two Monte Carlo algorithms of the Markovian type which solve the modified QCD evolution equations at the NLO level. The modifications with respect to the standard DGLAP evolution concern the argument of the strong coupling constant alpha_S. We analyze the z - dependent argument and then the k_T - dependent one. The evolution time variable is identified with the rapidity. The two algorithms are tested to the 0.05% precision level. We find that the NLO corrections in the evolution of parton momentum distributions with k_T - dependent coupling constant are of the order of 10 to 20%, and in a small x region even up to 30%, with respect to the LO contributions.Comment: 32 pages, 9 pdf figure

Elaboration of bioresorbable multilayered polymeric carriers for controlled doxorubicin release

W pracy przedstawiono wyniki badań uwalniania i degradacji in vitro do sztucznego płynu mózgowo- rdzeniowego (aCFS) dla wielowarstwowych matryc polimerowych zawierających doksorubicynę jako substancję leczniczą. Proponowany system terapeutyczny zbudowany jest z trzech warstw, tj. 2 zewnętrznych warstw kopolimeru glikolidu z ε-kaprolaktonem i 1 wewnętrznej warstwy kopolimeru glikolidu z D,L-laktydem z 10% zawartością cytostatyka. System wielowarstwowy utworzono przez kompresję w określonych warunkach: temperatury, nacisku i czasu. Postęp degradacji został potwierdzony przy pomocy zmian mikrostruktury łańcuchów metodą spektroskopii magnetycznego rezonansu jądrowego. Kinetykę uwalniania doksorubicyny z matryc jednowarstwowych i trójwarstwowych obserwowano przy pomocy spektroskopii UV-VIS. Zastosowanie trójwarstwowej matrycy pozwoliło na zmniejszenie początkowego wyrzutu leku z powierzchni nośnika polimerowego a tym samym zmniejszenie inhibicji uwalniania do 100 godzin eksperymentu.In this work the results of in vitro release and degradation to artificial cerebrospinal fluid solution (aCFS) from multi-layered polymeric matrices containing cytostatic drug were performed.. The proposed therapeutic system was constructed from three layers: the glycolide/caprolactone copolymer were used in two external layers and glycolide/D,L-lactide copolymer in internal layer containing 10-weight % of cytostatic agent.. Three-layered drug release system was made by compression at suitable conditions of time, temperature and pressure. The degradation of three-layered polymeric matrices was confirmed on the basis of changes in copolymer chain microstructure using high resolution NMR spectroscopy. Kinetics of doxorubicin release from mono- and three-layered matrices was observed by UV-VIS spectroscopy. Application of three-layered matrix may be used to reduction of burst effect from polymeric carrier surface and to reduction of inhibition effect of doxorubicin release observed in first stage from mono-layered matrix

The impact of the ban on spending weekly rest in the vehicle on transport planning in the eu

The working conditions of truck drivers and social legislation are both topical and political issues in the field of road freight transport. The contribution outlines problems which are linked to the observance of the ban on weekly rest in the vehicle. Based on the judgment, the Court of Justice of the European Union explicitly forbids drivers to take their regular weekly rest in the vehicle. The contribution identifies the impact of the ban on spending weekly rest in the vehicle on transport planning in the EU. The aim of the contribution is also to highlight the existing problems in international road freight transport sector in connection with insufficient number of truck parks with accommodation

Optimization of Soft Magnetic Properties in Fe-B and Fe-B-Si Amorphous Alloys Obtained by Melt Spinning Method

In the present paper the process of optimization of soft magnetic properties have been studied by applying different experimental techniques (magnetic measurements, electric measurements, X-ray analysis, and high-resolution electron microscopy observations). It has been shown that an increase in magnetic permeability after optimization annealing can be mainly attributed to annealing out of microvoids

Structural Relaxation and Crystallisation in Fe-Cr-Si-B and Fe-Cu-Cr-Si-B Amorphous Alloys

Structural relaxation, crystallisation and optimisation processes in soft magnetic amorphous alloys based on iron are examined by applying different experimental techniques: X-ray diffraction analysis, high-resolution electron microscopy, measurements of magnetic and electric properties (permeability, after-effect, resistivity). The presented results are discussed in terms of annealing out of microvoids, formation of a nanocrystalline phase and changes of effective magnetostriction constant

Streptococcus constellatus as an aetiological factor of extensive neck phlegmon complicated by sepsis - case study

Introduction. Mercury release in the environment is mainly the result of human activity, particularly from coal-fired power stations, residential heating systems, waste incinerators, and as a result of mining for mercury, gold and other metals, which have led to widespread global mercury pollution. Excessive exposure to mercury is associated with a wide range of adverse health effects, including damage to the central nervous system, digestive and immune systems, and to lungs, kidneys, skin and eyes. Objective. The main aim of the study is to summarize the selected mercury sources in the environment of the Slovak Republic, regarding waste incinerators, landfill waste, crematoria, chemical plants, rivers and soils. Brief description of state of knowledge. Although the neurologic symptoms of Minamata disease were identified sufficiently for specialists to classify mercury as the causative agent, the acceptance of mercury ́s environmental impacts will require several decades of research. Several new issues have arisen – the need for energy conservation leads to the use of fluorescent lighting, which contain mercury; emissions driven by increases in coal combustion, incineration and economic development have sent more mercury into the air, soil and water. Conclusions. Mercury is toxic to human health, posing a particular threat to the development of the child in utero and early in life. The systematic analytical controls of contaminants in water, soil and air are important. The installation of modern cleaning technologies to comply with the maximum emission level can substantially minimized the environmental impact of incinerators. Since human cremation is also an increasing practice, further research on mercury emissions is necessary

Structural Relaxation in Fe78Nb2B20Fe_{78}Nb_{2}B_{20} Amorphous Alloy Studied by Mössbauer Spectroscopy

It was shown that soft magnetic properties of $Fe_{78}Nb_{2}B_{20}$ amorphous alloy can be significantly improved by applying 1-h annealing at temperature 623 K (permeability increases even about 8 times). The Mössbauer Spectroscopy technique indicated that the optimized microstructure (corresponding to the maximum magnetic permeability) is free of iron nanograins and should be attributed to annealing out of free volume and a reduction of internal stresses i.e. to the relaxed amorphous phase